1. Field of the Invention
The present invention relates to an impact-sensing thermal insulation system.
2. Description of Related Art
Missiles, rockets, and other such vehicles use propellants that are often stored in pressure vessels within the vehicles. It is often desirable to thermally insulate such pressure vessels to protect the pressure vessels from aerodynamic heating during flight, which can undermine the structural integrity of the pressure vessels.
Moreover, it is important to avoid mechanically damaging pressure vessels. It is, however, inevitable that some damage will occur to such members during use. Sometimes it is not known that damage has occurred to a pressure vessel. In such situations, the pressure vessel may fail upon use without warning. At other times, it may be known that damage has occurred but it is not known whether the damage is extensive enough to compromise the structural integrity of the pressure vessel. Often, sophisticated testing is required to determine whether the pressure vessel is structurally sound for its intended purpose. Accordingly, it is often desirable to monitor the structural “health” of such pressure vessels so that the likelihood of a catastrophic failure can be minimized.
The structural integrity of composite pressure vessels, such as those made from materials comprising strands or filaments of structural fibers disposed in a polymeric matrix, may be particularly compromised if such a pressure vessel is mechanically damaged. Optical sensor arrays have been developed that can be embedded at discrete locations within a composite member to measure the internal strain of the member during use. Such sensors, however, provide no information as to the structural health of the member prior to use, because an unacceptable strain level may only be encountered during use. Moreover, these sensors fail to provide any information concerning external, impact-induced damage because they are disposed within the member.
While there are many thermal insulation systems well known in the art, considerable room for improvement remains.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.